I gotta question how regularly well serviced some of these poor cars are? and I mean a real service and not just a top up with oil and water..(if that!) lol. Any miss-treated abused car of this age will only be as good as the owner that maintains it and drives it in my opinion (or previous owner).
I have owned 5 5gtt's and not one has blown a head gasget or a turbo! All have been used as daily drivers apart from my current 5gtt, and all been no less reliable than any other car I've owned. (because they have been correctly set up) poor fueling and silly amounts of boost is going to be the most common accident waiting to happen with these cars (head gaskets are then blamed by these guys!) A rolling road tune is a good investment imo by a 5 specialist. Too many people buy them to run as maintenance free and cheap as humanly possible on a zero budget, to get the most fun for little cost!
This is where these poor old cars suffer imo, anyone thats looking....find one thats been well maintained.. regular service history all old MOT's to back up the history and an owner that doesnt run silly amounts of boost on a standard set up.
Most of the disaster stories are from DIY tuners, anyone looking to buy a 5... please be careful who's previous 'project' (disaster) your buying. They just add to spoiling the reputation of these great little cars. Dont think you will find a reliable 5gtt for under a grand! lol. £2k+ is where anything worth seeing starts at and thats still peanuts.
I saw far too many disasters when I was searching for another one a few years ago (to buy my current 5) I searched all over the country and most of the time, was lied to about the condition over the phone until I saw what was sitting on the drive! Some of these owners seriously beleive they are mint with the doors hanging off because theycan be 'easily fixed'! lol. Luckily one came up that was very well looked after, and its been a pleasure to own.. just my thoughts for the day..